Very important review, especially by emphasizing the low probability, but high, possibly catastrophic, impact of genetic evolution to infect humans. This is what public health is all about and currently the unsurveilled spread of H5N1 shows how deficient our public health capacity has become.
One correction - pigs are already getting infected. According to APHIS at the USDA while investigating positive cases of H5N1 in a backyard farming operation in Oregon a healthy pig was slaughtered and found to be systemically infected by H5N1. On October. 29, the USDA National Veterinary Services Laboratories confirmed one of the farm’s five pigs to be infected with H5N1, marking the first detection of H5N1 in swine in the United States. Continuing the lack of basic public health interventions, I am not aware of any ongoing surveillance of swine in farms around the country.
Thanks for your comment! You're right, I meant that we see sustained transmission among pigs, like with other flu viruses. I could have made that clearer.
Alas any infected swine is a significant red flag! They remain healthy; can have multiple concurrent influenza infections with genetic sharing facilitating adverse (for us) selection; and still there is no program for national infection surveillance. There could be transmission, is anyone looking for it?
A few links on the reuse of poultry waste as ruminant feed:
Some of these are old and some nations which once permitted poultry feces to be fed to livestock no longer permit it. I do not think that this duplicates any earlier links I would have sent on the topic.
BTW, you will notice there was a temporary ban on the use of chicken litter during the strongest worries about BSE (mad cow). There was a study which suggested that chicken which were fed cattle scrapes did not contract BSE but did pass it along in viable form. I have not seen a follow-up to that study, but there are now multiple studies showing that corvids pass viable Chronic Wasting Disease prions after eating infected deer.
One benefit that we have with pork production is that a lot of hogs are raised entirely inside with hygiene controls that limit exposure from outside sources. Once upon a time I worked in the nursery of a large hog farm and we had to shower into the barns, wear clothes provided to us, and shower out. They really worked hard to make sure there wasn't any contamination from the outside. The risk to most hog farms will be infected humans going to work with the virus and infecting the hogs.
I think her point was that when transmission among pigs themselves happens that we are closer to the potential of a human pandemic. Definitely, jumping fast any time influenzas wind up in pigs is very important for reducing human risk, hopefully, before transmission among pigs.
Something to keep in mind about the hog and cattle industries is that although the federal regulations call for waste to not be used and for foods for pigs to be cooked, they also permit states to decide what is waste and what is not. That is one reason that the warnings have been put out to NOT reuse poultry litter for other animals. In some states the state definitions do present that problem of used litter with droppings being reused , and bird droppings are a worrisome consideration, especially since many animals will eat them. Historically, there was a time when they were even mixed into cattle feed as an extra nutrient. I will see if i can get time to search for the refs on that, though i may have posted at least one in the past.
The response of the government to bird flu illustrates how dysfunctional the federal bureaucracy has indeed become. FDA (the F is food food) and Dept of Agriculture have two different remits. FDA is about food safety/human health. Ag is about protecting the farmers. Never worked and never will.
You think it's dysfunctional now, just wait a month. As the late Al Jolson said, "you ain't seen nothin' yet!"
Any day now, I expect Captain Brainworms to take to antisocial media to tell Americans to drink raw milk, kiss a chicken, and hug sick animals so they can develop "natural immunity." I only wish I were kidding.
Thanks yet again--this is a very helpful update. The Federal response to such concerns is, as you point out, already slow and inefficient. The new administration does not look as if it will foster improvements. One big question is how much illness and death we are willing to tolerate as "the cost of doing business."
Hugely helpful. Your closing lines are chilling, as the likelihood of this occurring now seems nil: “In the meantime, the U.S. government needs to take control of this outbreak. The time to prevent an H5N1 pandemic is now.”
Question: I get my eggs from a local farmer who sometimes does not wash them before delivering. Can H1N1 spread through handling the eggs or do I have to have contact with the bird itself? Thanks!!
Ha…good luck getting ahead of this given the incompetent folk that trump has nominated! You rightly say that now is the time to get ahead of this, but that absolutely will not happen with someone like Robert Kennedy in charge. AND remember, when trump’s gang took over prior to COVID - they had a playbook from Obama and they threw it out and ended up killing thousands! There has to be some way to forestall this new threat, but I’m afraid it will not happen with these incompetent fools in charge. This does sound highly pessimistic, but, as has been said, reality bites. 😔
One other thing for pet owners to avoid: freeze-dried raw meat treats. A cat in Oregon recently died from consuming contaminated treats. It was confirmed beyond all doubt that the treats were responsible and this particular batch was recalled, but of course that didn't remove all such treats from the market.
"This cat was strictly an indoor cat; it was not exposed to the virus in its environment, and results from the genome sequencing confirmed that the virus recovered from the raw pet food and infected cat were exact matches to each other," he said.
Thanks. Hard to know what that means with an n=1. I think avoiding all freeze-dried pet raw pet treats might be extreme for now. Being picky about what brands you buy, on the other hand, would not be a bad plan.
There are all sorts of cat treats that aren't raw. If one were talking about an animal who for some reason could only tolerate raw meat, that would be one thing. But I have no difficulty denying a particular sort of treat to my cat when there are alternatives!
Plus, this is a very responsible manufacturer. I happen to live in Oregon and I have heard nothing but good things about this company. If one were to do research to find the best place to buy these kinds of treats, I bet they would be right on the top of the list. There was not some sort of negligence that resulted in this contaminated product being sold. So being "picky about" the brand does not solve anything.
Before making your final choice do read up on what the animals who die of it go through, especially the ones who have it infect their brains. You do not want to later beat yourself up with “If only I had known.” Pubmed is quick way to find rigorous studies.
I would just like to point out that there are songbirds and other birds like doves and pigeons that have been infected with H5Nx HPAI (not necessarily H5N1) according to the UN Food and Agriculture Organization. This list was last updated in December 25, 2024.
I'm an avid birder and think often about birds that routinely fly from Canada to Central or South America, even some that migrate to Europe through the East Atlantic Flyway. Given the migratory nature of wild birds, are other countries seeing similar levels of H5N1, either in poultry or mammals?
There are other pets and domestic animals also at risk: goats, other members of Carnivora other than cats and dogs (though felines are at extreme risk of the neurological presentation), at least some rodents, pigs, etc.
I am so grateful that you and other brilliant scientists are not only staying on top of this, but have pledged to let us know if the time comes to take precautions to protect ourselves. I have no faith in the incoming administration’s commitment to science - or even in their ability to understand science - so am relying upon people like you and Michael Osterholm (I highly recommend his podcast to anyone not already listening!) to give us the critical data we need. It’s going to be a wild ride, I am afraid.
Very important review, especially by emphasizing the low probability, but high, possibly catastrophic, impact of genetic evolution to infect humans. This is what public health is all about and currently the unsurveilled spread of H5N1 shows how deficient our public health capacity has become.
One correction - pigs are already getting infected. According to APHIS at the USDA while investigating positive cases of H5N1 in a backyard farming operation in Oregon a healthy pig was slaughtered and found to be systemically infected by H5N1. On October. 29, the USDA National Veterinary Services Laboratories confirmed one of the farm’s five pigs to be infected with H5N1, marking the first detection of H5N1 in swine in the United States. Continuing the lack of basic public health interventions, I am not aware of any ongoing surveillance of swine in farms around the country.
Thanks for your comment! You're right, I meant that we see sustained transmission among pigs, like with other flu viruses. I could have made that clearer.
Alas any infected swine is a significant red flag! They remain healthy; can have multiple concurrent influenza infections with genetic sharing facilitating adverse (for us) selection; and still there is no program for national infection surveillance. There could be transmission, is anyone looking for it?
A few links on the reuse of poultry waste as ruminant feed:
Some of these are old and some nations which once permitted poultry feces to be fed to livestock no longer permit it. I do not think that this duplicates any earlier links I would have sent on the topic.
https://www.fao.org/4/x6518e/x6518e03.htm#:~:text=Lower%20levels%20(4%E2%80%937%25),apparently%20stimulate%20growth%20and%20appetite.
https://www.agric.wa.gov.au/livestock-biosecurity/prevent-ruminants-accessing-chicken-litter-and-organic-fertilisers-containing
https://www.poultryworld.net/the-industrymarkets/market-trends-analysis-the-industrymarkets-2/chicken-litter-in-livestock-feed-comes-under-scrutiny-in-us/
https://www.cambridge.org/core/journals/animal-science/article/abs/note-on-dried-poultry-manure-in-the-diet-of-the-growing-pig/ED87FD32F966228CF4501FCB2C489A2B
https://www.unmc.edu/healthsecurity/transmission/2024/04/30/is-chicken-feces-behind-the-bird-flu-outbreaks-in-cows-heres-what-to-know/
https://www.unmc.edu/healthsecurity/transmission/2024/04/30/is-chicken-feces-behind-the-bird-flu-outbreaks-in-cows-heres-what-to-know/
https://www.aces.edu/blog/topics/beef/feeding-broiler-litter-to-beef-cattle/https://extension.missouri.edu/publications/g2077
BTW, you will notice there was a temporary ban on the use of chicken litter during the strongest worries about BSE (mad cow). There was a study which suggested that chicken which were fed cattle scrapes did not contract BSE but did pass it along in viable form. I have not seen a follow-up to that study, but there are now multiple studies showing that corvids pass viable Chronic Wasting Disease prions after eating infected deer.
One benefit that we have with pork production is that a lot of hogs are raised entirely inside with hygiene controls that limit exposure from outside sources. Once upon a time I worked in the nursery of a large hog farm and we had to shower into the barns, wear clothes provided to us, and shower out. They really worked hard to make sure there wasn't any contamination from the outside. The risk to most hog farms will be infected humans going to work with the virus and infecting the hogs.
I think her point was that when transmission among pigs themselves happens that we are closer to the potential of a human pandemic. Definitely, jumping fast any time influenzas wind up in pigs is very important for reducing human risk, hopefully, before transmission among pigs.
Something to keep in mind about the hog and cattle industries is that although the federal regulations call for waste to not be used and for foods for pigs to be cooked, they also permit states to decide what is waste and what is not. That is one reason that the warnings have been put out to NOT reuse poultry litter for other animals. In some states the state definitions do present that problem of used litter with droppings being reused , and bird droppings are a worrisome consideration, especially since many animals will eat them. Historically, there was a time when they were even mixed into cattle feed as an extra nutrient. I will see if i can get time to search for the refs on that, though i may have posted at least one in the past.
The response of the government to bird flu illustrates how dysfunctional the federal bureaucracy has indeed become. FDA (the F is food food) and Dept of Agriculture have two different remits. FDA is about food safety/human health. Ag is about protecting the farmers. Never worked and never will.
You think it's dysfunctional now, just wait a month. As the late Al Jolson said, "you ain't seen nothin' yet!"
Any day now, I expect Captain Brainworms to take to antisocial media to tell Americans to drink raw milk, kiss a chicken, and hug sick animals so they can develop "natural immunity." I only wish I were kidding.
Thanks yet again--this is a very helpful update. The Federal response to such concerns is, as you point out, already slow and inefficient. The new administration does not look as if it will foster improvements. One big question is how much illness and death we are willing to tolerate as "the cost of doing business."
Or rather, what probability are we comfortable waging? This is THE big question right now.
Hugely helpful. Your closing lines are chilling, as the likelihood of this occurring now seems nil: “In the meantime, the U.S. government needs to take control of this outbreak. The time to prevent an H5N1 pandemic is now.”
Question: I get my eggs from a local farmer who sometimes does not wash them before delivering. Can H1N1 spread through handling the eggs or do I have to have contact with the bird itself? Thanks!!
Ha…good luck getting ahead of this given the incompetent folk that trump has nominated! You rightly say that now is the time to get ahead of this, but that absolutely will not happen with someone like Robert Kennedy in charge. AND remember, when trump’s gang took over prior to COVID - they had a playbook from Obama and they threw it out and ended up killing thousands! There has to be some way to forestall this new threat, but I’m afraid it will not happen with these incompetent fools in charge. This does sound highly pessimistic, but, as has been said, reality bites. 😔
Assuming kids don't pet animals, should families be concerned about outings to zoos or farms open to children visitors? Thanks.
Cattle are cattle whether they are dairy or beef cattle.
I know of a case that should raise more questions.
My relative has a grass fed beef cattle operation in west central Iowa.
In April of last year many of the cattle in his small herd appeared "unwell for several days"
No cattle died or became severely sick.
However, the father and son on this farm became mildly sick with cold like symptoms.
Both had pronounced conjunctivitis!
And to top it of their farm cat died overnight for no apparent reason.
There are very likely MANY more H5N1 human and cattle case across the country.
One other thing for pet owners to avoid: freeze-dried raw meat treats. A cat in Oregon recently died from consuming contaminated treats. It was confirmed beyond all doubt that the treats were responsible and this particular batch was recalled, but of course that didn't remove all such treats from the market.
Got a reference for that?
https://www.nbcnews.com/news/animal-news/northwest-naturals-pet-food-recalled-bird-flu-contamination-cat-dies-rcna185405
Whoops! Meant to copy/paste this quote:
"This cat was strictly an indoor cat; it was not exposed to the virus in its environment, and results from the genome sequencing confirmed that the virus recovered from the raw pet food and infected cat were exact matches to each other," he said.
Thanks. Hard to know what that means with an n=1. I think avoiding all freeze-dried pet raw pet treats might be extreme for now. Being picky about what brands you buy, on the other hand, would not be a bad plan.
There are all sorts of cat treats that aren't raw. If one were talking about an animal who for some reason could only tolerate raw meat, that would be one thing. But I have no difficulty denying a particular sort of treat to my cat when there are alternatives!
Plus, this is a very responsible manufacturer. I happen to live in Oregon and I have heard nothing but good things about this company. If one were to do research to find the best place to buy these kinds of treats, I bet they would be right on the top of the list. There was not some sort of negligence that resulted in this contaminated product being sold. So being "picky about" the brand does not solve anything.
Before making your final choice do read up on what the animals who die of it go through, especially the ones who have it infect their brains. You do not want to later beat yourself up with “If only I had known.” Pubmed is quick way to find rigorous studies.
I would just like to point out that there are songbirds and other birds like doves and pigeons that have been infected with H5Nx HPAI (not necessarily H5N1) according to the UN Food and Agriculture Organization. This list was last updated in December 25, 2024.
https://www.fao.org/animal-health/situation-updates/global-aiv-with-zoonotic-potential/bird-species-affected-by-h5nx-hpai/en
I'm so glad that I found you (& that I'm a paid subscriber of yours). Many thanks!
Could you discuss the state of vaccines under development? Would Kennedy allow them to be used?
Allow? Hell, the lunatic will probably try to have them banned.
I'm an avid birder and think often about birds that routinely fly from Canada to Central or South America, even some that migrate to Europe through the East Atlantic Flyway. Given the migratory nature of wild birds, are other countries seeing similar levels of H5N1, either in poultry or mammals?
Yes.
Not in dairy cattle, but in others, including donkeys in Egypt and horses in Mongolia. Wild animals all over.
There are other pets and domestic animals also at risk: goats, other members of Carnivora other than cats and dogs (though felines are at extreme risk of the neurological presentation), at least some rodents, pigs, etc.
Now horses:
https://www.news-medical.net/news/20250105/H5N1-bird-flu-spillover-to-horses-raises-fears-of-new-viral-strains.aspx
thank you Katelyn.
I am so grateful that you and other brilliant scientists are not only staying on top of this, but have pledged to let us know if the time comes to take precautions to protect ourselves. I have no faith in the incoming administration’s commitment to science - or even in their ability to understand science - so am relying upon people like you and Michael Osterholm (I highly recommend his podcast to anyone not already listening!) to give us the critical data we need. It’s going to be a wild ride, I am afraid.